The invention relates to a device for at least partially encapsulating a border of a substantially sheet shaped element, said device comprises a mould having at least two parts for pressing there between said element, said mould being provided with means for forming, when said element is pressed between parts of said mould, a cavity around said border, said device further comprising injection means for injecting a moulding substance into said cavity.
Such a device is generally used for encapsulating the border of, for example, windows for automobiles. The manufactured sheet of glass is brought between the parts of a mould in order to encapsulate at least a part of a border of the window. Generally flexible plastic gaskets are used for that purpose.
When the mould is closed and the sheet shaped element is pressed between the parts of the mould, there is formed a hollow cavity around the part of the border to be encapsulated. In said cavity a moulding substance is injected in order to form a ring of elastomer around the glass, which serves to make a junction, having preferably an aerodynamical profile, between the car body and the sheet of glass.
A drawback of the known device is that, due tot he fact that the used sheet shaped elements always show irregularities at their surface, e.g. thickness variation and changes of bending radius, the encapsulation can not correctly be realised.
As more and more automobile windows have bended surfaces in two directions, the encapsulation technique becomes more and more complex.
In the existing technique elastomer gaskets, such as rubber blocks, are used, which are embodied in the mould surfaces in order to form at least a part of the cavity. These gaskets also serve to prevent the flow of the moulding substance out of said cavity. These elastomer gaskets have the disadvantage of imperfect parting lines, since they tend to camber when to much pressure is applied thereon. Further they also need regular cleaning and maintenance, and their life time is limited. Due to these deficiences of the elastomer gaskets, leakages of the moulding substance are creating flashforming at the surroundings of the element to be encapsulated. These flashes need than to be removed, which implies additional costs and causes damages on the element to be encapsulated.